Fig. 1.

A: Na⁺ pump α- and β-subunit organization in the plasma membrane (PM). The locations of the antibody epitope amino acid sequences used for the generation of isoform-specific antibodies are indicated on the α-subunit. They are all located within a short segment on the large cytoplasmic loop between transmembrane segments TM4 and TM5 (41). B: structure of the Flag-tagged Na⁺ pump α₂-subunit NH₂-terminal segment used to generate α₂ dominant negative (DN) mice. This construct is expressed in the PM and causes greatly reduced PM expression of native α₂-Na⁺ pumps (the DN effect) in arterial smooth muscle (SM) cells (ASMCs) (51).